Assessment of Phytoecological Parameters of Forest Massifs in the Kwilu Province in the Democratic Republic of the Congo
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Asian Plant Research Journal 6(4): 8-18, 2020; Article no.APRJ.59032 ISSN: 2581-9992 Assessment of Phytoecological Parameters of Forest Massifs in the Kwilu Province in the Democratic Republic of the Congo Y. B. da-Musa Masens1, Koto-te-Nyiwa Ngbolua1,2, Mandung Masens3, John Makiadi Tambu Tembeni1 and Gédéon Ngiala Bongo1* 1Faculty of Science, University of Kinshasa, Kinshasa XI, Kinshasa, Democratic Republic of the Congo. 2University of Gbadolite, Gbadolite, Province of Nord-Ubangi, Democratic Republic of the Congo. 3Higher Institute of Medical Techniques of Lumbi, Province of Kwilu, Democratic Republic of the Congo. Authors’ contributions This work was carried out in collaboration among all authors. Author YBMM designed the study. Authors KNN and GNB wrote the first draft of the manuscript. Authors YBMM, KNN and JMTT managed the analyses of the study. Authors MM and GNB managed the literature searches. All authors read and approved the final manuscript. Article Information DOI: 10.9734/APRJ/2020/v6i430134 Editor(s): (1) Dr. K. S. Vinayaka, Kumadvathi First Grade College, India. Reviewers: (1) Tej Narayan Mandal, Tribhuvan University, Nepal. (2) Weydson Nyllys Cavalcante Raulino, University of Brasília, Brazil. (3) S. Jalajakshi, Bangalore Central University, India. Complete Peer review History: http://www.sdiarticle4.com/review-history/59032 Received 01 June 2020 Accepted 06 August 2020 Original Research Article Published 12 November 2020 ABSTRACT Rainforests constitute the great green heart of Africa and thus they present a unique combination of ecological, climatic and human interactions. The degradation of various forest ecosystems in mainly tropical regions and more particularly in sub-Saharan Africa has been a constant reality since the emergence of man. Faced to this almost alarming picture, most often linked to the countless economic challenges and calamitous management and confronted with unavoidable climate change, it seemed appropriate and imperative to assess the quantities of Air Biomass, sequestered carbon stocks, carbon equivalent and basal area produced by various forest massifs encountered in the Kwilu province. This study was carried out at the Kiyaka Agricultural Research Station _____________________________________________________________________________________________________ *Corresponding author: E-mail: [email protected]; Masens et al.; APRJ, 6(4): 8-18, 2020; Article no.APRJ.59032 located in the south of Kikwit. Five blocks of 100 m / 20 m were delineated using a 200 m long nylon wire divided into 10 m intervals. The system thus delimited made it possible to inventory all the trees, of which dbh measured at 1.30 m at chest height is ≥ 10 cm. The findings showed that species are divided into 11 orders, 42 genera and 19 families. The following systematic units are best represented in terms of number of plant species. These families are namely: Fabaceae, Malvaceae, Apocynaceae, Euphorbiaceae and Olacaceae, which together contain 26 plant species, while nine families are poorly represented. However, this reserve is threatened by its occupants on all sides; they do not want to clear large areas of forest for their field work. It is therefore urgent for INERA/Kiyaka officials to take the necessary measures for its full protection. Keywords: Phytoecology; forest massifs; Kwilu; Democratic Republic of the Congo. 1. INTRODUCTION (DRC) to access and gain carbon credits to an extend that this would participate in the The rainforests are the great green heart of temperature regulation of the atmosphere. It Africa, and present a unique combination of should be noted that forests sequester and store ecological, climatic and human interactions [1]. more carbon than any other terrestrial ecosystem Recently, there has been a surge of interest in and are an important natural brake on climate tropical forests, as there is increased change. This regulation would then allow to the appreciation of the rich biodiversity they host and reduction of currently increasing greenhouse the many roles they play in the functioning of the gases emissions as stipulated in the Kyoto Earth system at local, regional and global scales protocol [6]. The aim of this study was to assess [1]. However, Forests constitute an efficient different parameters, which can help in the carbon sink through actions like afforestation, preservation of existing forests and limits the forest management, forest management [2]. The emission of greenhouse gases. degradation of various forest ecosystems in tropical regions and more particularly in sub- 2. METHODS Saharan Africa has been a constant reality for decades [3]. 2.1 Study Area It was reported that "more than 200,000 years This study was carried out at the Kiyaka ago, men controlled fire and used it to burn dry Agricultural Research Station, which is located at tropical rainforests, most often to hunt game or 75 km in the South of Kikwit city in the Bandundu drive away predators [4]. Currently, there are province and it covered 3250 ha. Its geographical only less than 8% left and the majority of them coordinates are presented as follows: 5° 16' and are located in mountainous and/or difficult to 5° 24' South latitude, 18° 57' and 18° 43' East access areas. Faced to this alarming picture, longitude. The altitude varies between 400 to 509 most often linked to the countless economic m in the valley and 735 m at plateau level. challenges and calamitous management. This management is confronted to the unavoidable 2.2 Methods climate change issue, which seemed appropriate and imperative to assess the quantities of Above Five blocks of 100 m/20 m were delineated using ground Biomass (AGB), sequestered carbon a 200 m long nylon wire divided into 10 m stocks, carbon equivalent and basal area intervals. With this delimitation, it was possible to produced by various forest massifs) encountered inventory all trees, of which the dbh measured in the Kwilu district (Kwilu province). It is 1.30 m from the chest height. Thus, each species necessary to know that the implementation of having a dbh ≥ 10 cm was identified and with improved management practices to build up GPS, the position along with geographical carbon stocks in terrestrial ecosystems is being a coordinates was collected. proven technology to reduce the concentration of Carbon dioxide in the atmosphere [5]. Since we could not directly measure the diameter of each of these trees in the field, hence, the The knowledge of these parameters, in particular circumference was measured at 1.30 m from the sequestered carbon and its equivalent, the ground. For shafts with buttresses and/or aboveground biomass and basal area produced, deformations at this level, these measurements will help the Democratic Republic of the Congo were taken above the buttress or deformation. 9 Masens et al.; APRJ, 6(4): 8-18, 2020; Article no.APRJ.59032 Fig. 1. Map of Kiyaka Agricultural Research Center For botanical characterization indices, including 3. RESULTS AND DISCUSSION relative species density (DeR) and relative family density (DfR), were calculated as described by 3.1 The Flower of the Forest Massif Masens [7]. Studied = 100 (1) The floristic inventory listed 48 species, which were distributed into 11 orders, 19 families and = (2) 42 genera. The families of Fabaceae, Malvaceae, Apocynaceae, Euphorbiaceae and Olacaceae had each 26 species. While the The diameter classes of all species with a dbh ˃ following nine families, Annonaceae, Ebenaceae, 10 cm present in different surveys were Irvingiaceae, Lecythidaceae, Cecropiaceae, measured using a tape measure and grouped Rubiaceae, Sapotaceae, Ulmaceae and into different classes. Eco-sociological groups Verbenaceae were poorly represented. were differentiated as described in previous studies. Leaf size types were defined from Table 1 presents the floristic list of the Raunkiaer's classification [8,9]. For biological studied area along with different parameters types (BT), we used Raunkiaer's classification used. (1934), adapted to tropical regions by Belesi and Habari along with the types of diaspore dissemination were determined [8,9]. The floristic inventory listed 48 species, which were distributed into 11 orders, 19 families and 2.3 Data Analysis 42 genera. The families of Fabaceae, Malvaceae, Apocynaceae, Euphorbiaceae and The statistical analyses of the data were carried Olacaceae had each 26 species. While these out using the SPSS 14.0 software. It allowed us families, Ebenaceae, Rubiaceae, Ulmaceae and to know if the p-value value is ≤ 0.05, the Verbenaceae were poorly represented in terms parameters compared are correlated and if the p- of species. value values are ≥ 0.05, we conclude that there is no correlation between the parameters taken 3.2 The Relative Density into account. The ArcGIS and QGIS software were used to produce the map and to spatially The relative density of collected specimens in the distribute the species. study area is presented in the Table 2. 10 Masens et al.; APRJ, 6(4): 8-18, 2020; Article no.APRJ.59032 Table 1. Floristic inventory of Kiyaka massif forest Scientific names of species Number of dbh ST (m2) Aerial biomass Stored Carbon (t/ha) Equivalent C (t/ha) specimens (cm) (t/ha) Chave Pearson Chave Pearson Chave Pearson Alstonia boonei 12 218 0,35 13,23 10,6 6,22 4,98 22,81 18,27 Angylocalyx margininervatus 5 108 0,22 9,86 5,8 4,63 2,73 16,99 9,99 Anonidium mannii 8 421 1,63 100,13 31,52 47,06 14,81 172,58 54,32 Barteria nigritiana var. fistulosa 5 66 0,07 2,03